The report also revealed that Mr Barnes' client, whom he had been due to pick up from Elstree in Hertfordshire, advised him not to make the journey from Redhill Aerodrome in Surrey.

The report said: "At 0718hrs, the client called the pilot to discuss the weather. The pilot said he thought the weather might clear earlier than forecast. The client said he would drive to Elstree and call the pilot to keep him advised.

"At 0731hrs, having noticed how poor the weather was during his journey, the client called the pilot to suggest that he did not take off until he (the client) had reached Elstree and observed the weather. The pilot replied that he was already starting the engines.

"The client stated that he repeated his suggestion that the pilot should not take off."

He sent the client another message at 7.29am which stated: "I'm coming anyway will land in a field if I have to."

Mr Barnes' aircraft hit the crane and plummeted to the ground close to Vauxhall station.

He narrowly missed a new apartment block called The Tower, in St George's Wharf, to which the crane was attached as he crashed in Wandsworth Road.

An inquest into his death at Southwark Coroner's Court was earlier told he had been flying from Redhill to Elstree when he requested permission to divert.

Pedestrian Matthew Wood, 39, was also killed as he was walking to work.